Single in-line memory modules; i.e., "SIMM", represent a high density, low profile single in-line package for electronic components such as dynamic random access memory integrated circuit components. A plurality of these components can be mounted in line on a circuit panel whose height is little more than the length of the components themselves. The circuit panels can in turn be mounted on a printed circuit board daughter-card which can then be mounted on a printed circuit board mothercard. The spacing between adjacent daughtercards would then need to be only slightly greater than the height of the individual circuit panels or single in-line memory modules.
Hereto before circuit panels have been used in which the circuit traces on one side or surface are duplicated and electrically connected to traces on the opposite surface with the traces on both surfaces being in direct alignment with each other. Accordingly the sockets, known as "SIMM" sockets, such as disclosed in U.S. Pat. No. 4,973,270 have terminals which include opposed beams commoned to a single lead to provide redundant electrical engagement to each of the two commoned traces, one on each surface on the panel.
In response to industry's needs, we proposed, as disclosed in U.S. Pat. No. 5,082,459, to electrically isolate circuits and traces on opposite surfaces of the circuit panel so that additional electronic components can be mounted thereon and to provide a SIMM socket having electrically separate terminals on both sides of the panel receiving slot to engage the traces on both surfaces.
We now propose to incorporate an internal electrical ground plane along the length of the socket to further enhance the capabilities of the socket for high speed electrical application. The ground terminals will be spaced interstitially between the signal terminals where the ground terminals will interface with the ground plane then to the printed circuit board and the signal terminals will interface to the printed circuit board.